


Close Careful Attention

by withpractice_ff



Series: Our Knuckles are White [2]
Category: Marvel Cinematic Universe, The Avengers (Marvel Movies)
Genre: Collars, Kissing is better than talking, M/M, Science Boyfriends
Language: English
Status: Completed
Published: 2014-01-04
Updated: 2014-01-04
Packaged: 2018-01-07 12:07:15
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,918
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1119644
Author URL: https://archiveofourown.org/users/withpractice_ff/pseuds/withpractice_ff
Summary: <blockquote class="userstuff">
              <p>Bruce is having feelings.  Tony is having sexy feelings.  Natasha is ambivalent and also unsurprised.</p>
            </blockquote>





	Close Careful Attention

**Author's Note:**

> Further fill for the [kink meme prompt](http://avengerkink.livejournal.com/9218.html?thread=19320578#t19320578):
> 
> _By the power of SCIENCE!, Tony and Bruce invent a collar that prevents Bruce from Hulking out during sex. Naturally, they celebrate by putting it to use. A lot._
> 
> _Bruce also discovers that he likes to wear the collar sometimes when he’s going about his daily life. Like if it’s a stressful day or he really needs to concentrate in the laboratory. Unexpectedly glimpsing that Bruce is wearing the collar under his normal shirt is a massive, instant turn-on for Tony, both because he associates it with sex and because it gets him in a possessive mood. Bruce may or may not enjoy this side effect of the collar as well._
> 
> _Bonus: Another Avenger notices Bruce’s collar and asks what it’s for._

  


* * *

  


“I can be discrete,” Tony had said.

Bruce hadn’t really believed him.

  


* * *

  


Navigating interactions with Bruce after a transformation can be difficult. Tony never quite knows what to expect when Bruce comes to--if Bruce is going to be tired but relieved, happy that they’ve once again saved the day, or if it’s going to be one of those times when Bruce wakes up quiet and sullen, his eyes dark and his mood darker.

“So that was fun,” Tony tries, now that they’re alone. Today’s one of the bad days; Bruce had retreated into himself the moment Tony gently shook him awake. Tony never knows what the difference is--what has Bruce waking up triumphant or defeated-- and he’s never asked. This isn’t really his area, this brooding melancholy, but Bruce’s silence is becoming oppressive and Tony will gladly settle for the sound of his own voice if Bruce doesn’t feel like engaging. So he presses on, “I like that in his desperation, Doom’s increasingly willing to try any batshit idea that crosses his mind. I’m sort of looking forward to seeing what he’ll come up with next, frankly. Anthropomorphic staplers? Sentient flan? Rabid bunnies? We should start a pool.”

Bruce, sagged against the wall of the elevator, shrugs and makes some sort of noise in the back of his throat that is maybe supposed to be a laugh. Tony’s going to assume it was a laugh, because that was funny, goddamn it. Sentient flan, that’s fucking _gold_.

The doors ding open when they reach the lab, and Bruce pushes himself upright with a grimace, like moving is the worst thing that’s ever happened to him. Tony watches him, weighing his options, and when he decides that Bruce could use some time alone, he’s pretty sure it’s because Bruce would actually benefit from some space and not because Tony’s being selfish and cowardly.

“I’m going to grab some food,” Tony offers, leaning against the frame of the elevator. “You want anything?”

Bruce shrugs again, walking further into the lab. It’s not a particularly decisive gesture, which is kind of irritating, but Tony doesn’t like how worn out he looks, so alright, he will procure a mess of proteins and carbs and make sure Bruce eats enough of it to put some color back in his face. This is something tangible, something quantitative, and Tony likes problems he knows how to solve.

“Surprise you, got it. See you in thirty?”

Bruce throws him a wave, already pulling up the results from the test he’d been running before Doom decided to unleash his laser-bat-things on Midtown. Tony waits another beat, until he sees a familiar, thoughtful crease wrinkling Bruce’s forehead, and that’s close enough to normal that Tony doesn’t feel like a total asshole in leaving him to his own devices.

Another ding, and Tony disappears as the elevator doors slide shut. Bruce closes his eyes, takes a deep breath and exhales it slowly. He’s not sure if Tony’s just being Tony, carefully avoiding any situation that might call for introspection, or if he’s becoming unexpectedly perceptive, but either way, Bruce is grateful to have a minute alone.

Sometimes, the change into the Other Guy feels too easy, too welcome. Tony would probably have a thing or two to say about that, about how Bruce needs to worry less and embrace his inner rage monster more, and Bruce is frankly not in the mood for it. Which maybe Tony gets, because he’s never started in on it on days like today, when Bruce especially doesn’t want to hear it.

Bruce shakes his head, pushing thoughts of Tony out of his mind. He spends a lot of time thinking of Tony lately--too much, maybe. He hasn’t decided yet, and he chooses not to examine that indecision too closely. Instead, he turns his mind back to this last batch of results, trying to immerse himself in his work. But he’s unable to concentrate, his thoughts again and again returning to that moment this afternoon when he’d first started to change, that split second of adrenaline and terror and _relief_ , when he stopped being Bruce Banner and became something else, something _more_.

He closes his eyes and takes in another deep breath, letting it out slowly through his nose. His mind goes carefully, purposefully blank. It’s like floating, almost, and it’s nice. He opens his eyes, and his next breath comes a little easier than the last. He inhales again, easier still, and realizes that his hand is fisted around the collar Tony made for him, his thumb tracing a circuit against the soft leather. For a second its appearance in his hand is completely baffling, but then he remembers the last time he wore this cardigan just a few days ago, Tony slipping the collar into the pocket with a wicked smile and a slap on his ass.

He stares at it for a moment, feeling a rush of emotions that have nothing to do with the Other Guy, and then he gives in and puts it on, its weight around his neck familiar and grounding. He turns back to his data, and this time the numbers come easily into focus, his mind engaging with the task at hand. It’s not long before he’s fully absorbed in his calculations, and so he doesn’t immediately notice when Natasha enters the lab.

“Ahem,” she says dryly, and Bruce startles, looking up to find her standing across the table from him, arms folded across her chest and one hip canted against the counter beside her. She looks vaguely amused.

“Oh. Um, hi.”

“Dr. Banner.”

Bruce frowns, feeling a moment of displacement as he tries to figure out when Natasha arrived and what she’s even doing here. “What, uh-- What can I do for you?”

“I came to drop off this,” she says, and places a metal canister on the table between them. “Special delivery.”

“I heard they’re part bat?” Bruce asks, eying the canister warily.

“That’s for you to figure out, Doctor. I just shoot the things.”

“Is it dead?”

Natasha shrugs. “A bullet blew through its chest, so I certainly hope so.”

Bruce nods and turns to grab some gloves from the counter behind him. When he turns back around, he notices Natasha staring fixedly at his neck. She raises an eyebrow when he notices her looking, and all at once he remembers that he’s still wearing the collar. He can feel his face flushing red.

“So uh, I’m going to open this,” he warns her, hoping to draw her attention back to Doom’s abomination. And also, he really wants to open it.

Natasha knows very well that even if she asked, Bruce isn’t going to tell her, so she lets him think he’s distracted her and turns her eyes back to the canister. “I’ll be sure to shoot it if it starts careening around the room.”

The laser-bat-thing doesn’t careen around the room. It is well and truly dead, and it lies motionless on the steel table top when Bruce slides it out of the container. Natasha lets herself relax as Bruce starts probing it, pulling up a chair as Bruce asks JARVIS to run a biometric scan. She watches him work and considers the collar looped around his neck. She’s never seen him wear jewelry before, of any sort, and he’d been quick to distract her when he noticed her noticing it. Something private, then.

That’s about as far as she’s able to work it out when the elevator doors ding open and Tony Stark bursts in, carrying two bags of take out and crowing, “Honey, I’m home!”

“Agent Romanov brought us a present,” Bruce says, letting Tony know they’re not alone before he can say something incriminating.

And Tony, dropping the takeout onto an available workbench, is about to make a crack about the wisdom in accepting gifts from a super spy, but then he turns to look at Bruce and immediately his eyes find the collar around Bruce’s neck, and any joke he was about to make flies completely out of his head. He’s seen Bruce wearing that collar probably a hundred times, but never when he wasn’t expecting it, never with someone else there to see it.

“So hey, Bruce, come back to the office with me for a quick sec.”

“What? Why?” Bruce gestures to the laser-bat. “Come look at this.”

“Yeah yeah, of course, but first I gotta show you this thing. In the office.”

Bruce looks dubious for a second, but then he remembers all over again that he’s wearing the collar and a bright red flush creeps up into his cheeks. Natasha doesn’t miss it, but she keeps her face impassive, not wanting to influence whatever’s going on here.

Tony doesn’t wait for Bruce to respond, grabbing him by the wrist and pulling him toward the door. Over his shoulder he tells Natasha, “We’ll be just a minute, but feel free to show yourself out.”

Once in the office, Tony shuts the door behind them, and Bruce hears the click of the lock as he’s pushed against the flat pane of wood. “JARVIS, block the windows.”

“What are you doing?” Bruce hisses, very aware that Natasha’s just a room away.

Tony brings up a hand to curve gently around Bruce’s neck. “You’re wearing it.”

Bruce bites his lip, not entirely sure he wants to explain to Tony why he felt moved to put the collar on in the first place. But there’s something in Tony’s eyes, in the soft touch of his fingers as the trace they line of the collar, and so Bruce says, “I thought it might help me feel a bit more grounded.”

“Did it?” Tony asks, his other hand sliding slowly down Bruce’s chest. Bruce nods, swallows audibly, and Tony lowers his voice when he asks, “And how did it feel to have Natasha see you wearing it?”

Bruce closes his eyes as one of Tony’s legs works its way between thighs, tipping his head back against the door. Tony’s lips immediately avail themselves of the exposed skin of Bruce’s neck, and Bruce quietly admits, “I was worried she’d know.”

“Know what?” Tony asks, but the question must be rhetorical, because he fuses his mouth to Bruce’s before giving him a chance to respond. His kiss is hungry, possessive, and already Bruce’s body is responding. When they part, Tony presses his lips to Bruce’s ear and whispers, “Were you worried she’d take one look at that collar and know that it marked you as mine?”

Bruce lets out a hot gust of air against Tony’s neck. Though Tony has implied that he has a specific kink for the collar--beyond its obvious implications of sex--they’ve never actually talked about it. This falls pretty well in line with what Bruce had assumed, but to hear those words from Tony’s mouth, for him to make a claim to Bruce so explicitly-- it’s maybe the closest either of them has come to admitting how deep this thing between them runs.

Tony shifts against him, pressing his hard-on against Bruce’s thigh, and Bruce lets out another shaky exhalation and confirms, “Yes.”

Then Tony’s kissing him again, fumbling with Bruce’s belt with one hand and his own with the other. Bruce is still wearing the latex gloves from earlier, and when he moves to take them off, Tony pulls away from him long enough to say, “No, leave them on; I’ve got you.”

So Bruce lets his hands fall to his sides, palms flat against the door, and lets Tony ease him out of his boxers. This probably isn’t a good idea, with Natasha just a few feet away from them on the other side of the door, but Tony’s hands on him feel good, make him feel tethered to his body the same way the collar had helped to bring him back to himself. Tony’s body is solid against him, warm and real, and Bruce lets out a soft moan when Tony brings their erections together in one curled hand.

“Ssshhh,” Tony instructs, bringing his other hand up to cover Bruce’s mouth. Bruce licks at his fingers, and Tony drops his head to Bruce’s shoulder, biting at the fabric of his shirt and stifling a moan of his own.

And then Tony drives his hips forward, thrusting into his hand and against Bruce. The mixture of sweat and pre-come isn’t quite adequate lubrication, but he doesn’t seem to care, setting a pace that’s hard and fast, the jerks of his wrist timed with the thrusts of his hips.

“Jesus,” he breathes, voice low, his words hot on Bruce’s neck. He mouths at the collar for moment, pressing his teeth into the leather, then continues, “You looked so fucking good, wearing this thing like you had no idea what it would do to me. Couldn’t wait to get my hands on you.”

“Clearly,” Bruce manages, though his hips are moving in time with Tony’s, just as desperate.

“So gorgeous,” Tony says, and though it’s not the first time he’s said it, Bruce still isn’t used to hearing it. Tony keeps whispering his filthy nothings, and Bruce tunes him out, focusing on Tony’s hand around him, Tony’s thigh pressed hard against his own, Tony’s breath on his skin. He lets Tony’s voice fade into a pleasant hum, lets himself do nothing but feel.

Tony’s hips start to jerk erratically, and he buries his face in Bruce’s neck as he comes, letting out these quiet, sighing whimpers as he spends over his fist, over Bruce. The extra lubrication lets him work his hand over Bruce more quickly, and then Bruce is coming too, biting down on Tony’s fingers, still at his mouth.

“You should surprise me with this more often,” Tony says, brushing his thumb along the collar one last time before peeling himself off of Bruce. “Jesus Christ.”

“We’ll see,” Bruce replies noncommittally, then warily looks down at himself to assess the damage. Most of the mess is over Tony’s hand, which Tony’s presently wiping up with some tissues. Pulling off his gloves, he figures maybe there’s like a ten percent chance Natasha won’t realize what they were up to in here.

Still, he can’t help but feel that it was worth it. He feels good, more like himself, the tension he’d felt after his transformation completely drained out of him. Tony saunters over to him looking incredibly self-satisfied and pulls him in for one more deep, lingering kiss before pulling the door open and stepping out in the the lab.

“Hey!” Tony says, pointing an accusing finger at Natasha. She’s perched on a workbench, legs crossed and a fork full of spicy basil noodles on its way to her mouth. “No one invited you to stay for dinner.”

She shrugs, nudging the carton of pad see ew in Bruce’s general direction. He walks over warily, expecting some sort of trap, and Natasha says, “If you hadn’t kept me waiting, maybe you could have stopped me from raiding your take-out.”

“Seems unlikely,” Bruce says, looking through the bags for a plastic fork.

“I said maybe,” Natasha agrees. Tony’s wandered over to the table, eyeballing the laser-bat with obvious curiosity, and Jesus, he didn’t even remember to zip up his fly. If she was already pretty sure before they disappeared into the office, there’s certainly no doubt in her mind now. So she swallows her noodles and says, “So the collar, it’s a sex thing?”

Bruce drops his fork, and Tony goes wide-eyed and suspiciously silent.

“I don’t need the details,” she clarifies, “but if you two are fooling around, Clint owes me fifty bucks.”

“Oh god, you guys were taking bets?” Bruce mutters, and picks a fresh fork out of the bag.

“Just me and Clint; don’t worry, we’re not going to tell anyone.” She pauses, takes another bite of noodle, then adds, “Though I’m not sure why you’re hiding it.”

The two men share a look across the room, and for a moment Natasha worries that perhaps she’s hit a sore spot. But then Tony clears his throat, clearly uncomfortable, and says, “We weren’t hiding it, exactly. It’s just, ah, things have been going surprisingly well”--he looks over to Bruce for confirmation, who nods--”and we didn’t want to say anything to anyone until we knew where it was going. And also, we didn’t want to fuck it up with third-party interference. Or I didn’t, at least.”

Natasha looks over to Bruce, and he confirms, “Sounds about right.”

“Well, for whatever it’s worth, your secret is safe with me.”

“And Clint,” Tony adds, with more than a little snark.

“Yes, clearly,” she says, then sets her noodles down on the bench and moves to her feet. “So can we get back to the laser-bat? I would actually like to go home at some point this evening.”

Bruce shoves a last fork full of food into his mouth then walks over to Tony, who hands him another pair of gloves. JARVIS completed his scans while they were indisposed and found nothing dangerous active in the body, so onto the dissection. Tony stands close over his shoulder as he works--closer than he would have, had Natasha not called them out earlier--asking questions and handing him tools and making mostly helpful observations, and when he brings his hand to Bruce’s neck, thumb gently running the line of the collar, Bruce doesn’t mind at all.


End file.
